This invention relates to a device for subculturing inoculum from a standard culture bottle, with the device being utilized generally as a substitute for individual petri dishes or plates. The device includes an arrangement which supports a media gel, such as agar, for culturing the inoculum withdrawn from a standard culture bottle, together with an absorbent fiber disc mounted on the media gel so that the disc will absorb the inoculum and maintain a substantial measured portion of the inoculum adjacent the culture media for the culturing procedure. In addition, the device includes a needle mounted in fixed fashion in the device for penetrating the septum of a standard culture bottle for withdrawing the inoculum for the blind subculturing procedure.
The arrangement is such as to eliminate the use of the usual separate needle and syringe for withdrawing the inoculum from the standard culture bottle, and placing it on a standard petri plate or dish for the subculture procedure. By having an automatic procedure wherein the mounted needle of the device is inserted in the septum of the culture bottle, the culture bottle inverted together with the device of the invention, the disc on the media surface is saturated with inoculum in the desired quantity. With further inverting of the bottle and subculture device of the invention, the subculture device can then be removed from the upright culture bottle without any further activity and without the need for separate materials and arrangements for this transfer procedure.
By eliminating the need for a separate syringe and needle, of course, the problem of contamination is reduced substantially. That is, as will be appreciated by practitioners-in-the-art, the use of a separate syringe and needle for penetrating the septum of a standard culture bottle and placing an inoculum sample on a media gel, and subsequently closing the plate containing the media gel, there is a much greater opportunity for contamination of the subculture being reviewed.
As a further feature of the invention, the device may be maintained on the culture bottle in a manner wherein once the standard culture bottle and device have been inverted and then re-inverted, the standard culture bottle with the device and its needle inserted therein may be replaced into the incubator without removal of the device, in accordance herewith from the standard culture bottle. In this respect, the device of the invention includes a removable cap containing the culturing media and the saturated disc containing the absorbed inoculum. The cap may be momentarily removed for inspection, as required. The latter procedure would be utilized, generally, as will be understood by practitioners-in-the-art, if a terminal subculture procedure is being carried out. For an intermediate subculture, the device of the invention would be removed from the bottle, capped and incubated separately. For this reason, the invention includes a peel-off numbered label for marking the bottle so as to maintain a connection between the device of the invention which has been removed from the standard culture bottle, and the bottle itself.
In accordance with a further feature of the invention the removable cap may be a conventional petri plate or dish. The device of the invention is configured adjacent the top and bottom so as to receive a conventional petri dish as the cap therefor, if desired.
Preferably, the device will be comprised of a transparent material so that the contents may be observed. Preferably, the material will be a transparent resin, and may be, for example, a polystyrene, a polycarbonate or methyl methacrylate. The culture media will be selected, as will be understood, depending upon the culturing that is being carried out. An agar gel is representative of one culture media which may be utilized. The absorbent disc on the culture media for absorbing the inoculum may be comprised of, for example, an inert paper fiber. Its dimensions will be selected so as to maintain a predictable amount of inoculum intimate with the gel surface for incubation. As will be appreciated, the device is a throw-away device and is comprised of materials which are inexpensive for this purpose. In addition, the simplicity of arrangement is such that the device may be manufactured by mass production techniques making it commercially attractive.
Other objects and advantages of this invention will now be described in the following detailed description the accompanying drawing, and the appended claims.